STFU
STFU has 2 meanings
Super Time Force Ultra
A side-scrolling (platformer) game that includes dinosaurs, robots, and traveling through time; allows players to play as characters from other games, such as Team Fortress 2 and Left 4 Dead.
Example
The third level of STFU is so hard!
STFU is a crass way to succinctly tell someone you do not want to hear what they have to say. Typically, angry people use it when texting or messaging online and on social media.
There are many ways to tell someone to be quiet. If you want to shut someone up without swearing, you can use SU, S/U, or STFD to make their request more politely. Or, a creative option is "find your silence." Another crass option that includes h*** instead of f*** is STHU.
An example of when you might send "STFU" is when a person won't stop making fun of you after an embarrassing fail. Or, your older brother may be lecturing you, and you are no longer in the mood to hear it.